@@ -939,6 +939,7 @@ struct fib {
*/
struct list_head fiblink;
void *data;
+ u32 vector_no;
struct hw_fib *hw_fib_va; /* Actual shared object */
dma_addr_t hw_fib_pa; /* physical address of hw_fib*/
};
@@ -2098,6 +2099,7 @@ static inline unsigned int cap_to_cyls(sector_t capacity, unsigned divisor)
#define AAC_OWNER_FIRMWARE 0x106
const char *aac_driverinfo(struct Scsi_Host *);
+void aac_fib_vector_assign(struct aac_dev *dev);
struct fib *aac_fib_alloc(struct aac_dev *dev);
int aac_fib_setup(struct aac_dev *dev);
void aac_fib_map_free(struct aac_dev *dev);
@@ -90,6 +90,28 @@ void aac_fib_map_free(struct aac_dev *dev)
dev->hw_fib_pa = 0;
}
+void aac_fib_vector_assign(struct aac_dev *dev)
+{
+ u32 i = 0;
+ u32 vector = 1;
+ struct fib *fibptr = NULL;
+
+ for (i = 0, fibptr = &dev->fibs[i];
+ i < (dev->scsi_host_ptr->can_queue + AAC_NUM_MGT_FIB);
+ i++, fibptr++) {
+ if ((dev->max_msix == 1) ||
+ (i > ((dev->scsi_host_ptr->can_queue + AAC_NUM_MGT_FIB - 1)
+ - dev->vector_cap))) {
+ fibptr->vector_no = 0;
+ } else {
+ fibptr->vector_no = vector;
+ vector++;
+ if (vector == dev->max_msix)
+ vector = 1;
+ }
+ }
+}
+
/**
* aac_fib_setup - setup the fibs
* @dev: Adapter to set up
@@ -151,6 +173,12 @@ int aac_fib_setup(struct aac_dev * dev)
hw_fib_pa = hw_fib_pa +
dev->max_fib_size + sizeof(struct aac_fib_xporthdr);
}
+
+ /*
+ *Assign vector numbers to fibs
+ */
+ aac_fib_vector_assign(dev);
+
/*
* Add the fib chain to the free list
*/
@@ -156,8 +156,8 @@ static irqreturn_t aac_src_intr_message(int irq, void *dev_id)
break;
if (dev->msi_enabled && dev->max_msix > 1)
atomic_dec(&dev->rrq_outstanding[vector_no]);
- aac_intr_normal(dev, handle-1, 0, isFastResponse, NULL);
dev->host_rrq[index++] = 0;
+ aac_intr_normal(dev, handle-1, 0, isFastResponse, NULL);
if (index == (vector_no + 1) * dev->vector_cap)
index = vector_no * dev->vector_cap;
dev->host_rrq_idx[vector_no] = index;
@@ -448,36 +448,20 @@ static int aac_src_deliver_message(struct fib *fib)
dma_addr_t address;
struct aac_fib_xporthdr *pFibX;
u16 hdr_size = le16_to_cpu(fib->hw_fib_va->header.Size);
+ u16 vector_no;
atomic_inc(&q->numpending);
if (dev->msi_enabled && fib->hw_fib_va->header.Command != AifRequest &&
dev->max_msix > 1) {
- u_int16_t vector_no, first_choice = 0xffff;
-
- vector_no = dev->fibs_pushed_no % dev->max_msix;
- do {
- vector_no += 1;
- if (vector_no == dev->max_msix)
- vector_no = 1;
- if (atomic_read(&dev->rrq_outstanding[vector_no]) <
- dev->vector_cap)
- break;
- if (0xffff == first_choice)
- first_choice = vector_no;
- else if (vector_no == first_choice)
- break;
- } while (1);
- if (vector_no == first_choice)
- vector_no = 0;
- atomic_inc(&dev->rrq_outstanding[vector_no]);
- if (dev->fibs_pushed_no == 0xffffffff)
- dev->fibs_pushed_no = 0;
- else
- dev->fibs_pushed_no++;
+ vector_no = fib->vector_no;
fib->hw_fib_va->header.Handle += (vector_no << 16);
+ } else {
+ vector_no = 0;
}
+ atomic_inc(&dev->rrq_outstanding[vector_no]);
+
if (dev->comm_interface == AAC_COMM_MESSAGE_TYPE2) {
/* Calculate the amount to the fibsize bits */
fibsize = (hdr_size + 127) / 128 - 1;
This is a note to let you know that I have just added a patch titled aacraid: Fix RRQ overload to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue This patch is scheduled to be released in version 4.2.8-ckt7. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 4.2.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From 0eb9590d5a6c6a84fd044f77cbf2c9c7057db827 Mon Sep 17 00:00:00 2001 From: Raghava Aditya Renukunta <raghavaaditya.renukunta@pmcs.com> Date: Wed, 3 Feb 2016 15:06:00 -0800 Subject: aacraid: Fix RRQ overload commit 3f4ce057d51a9c0ed9b01ba693df685d230ffcae upstream. The driver utilizes an array of atomic variables to keep track of IO submissions to each vector. To submit an IO multiple threads iterate through the array to find a vector which has empty slots to send an IO. The reading and updating of the variable is not atomic, causing race conditions when a thread uses a full vector to submit an IO. Fixed by mapping each FIB to a vector, the submission path then uses said vector to submit IO thereby removing the possibly of a race condition.The vector assignment is started from 1 since vector 0 is reserved for the use of AIF management FIBS.If the number of MSIx vectors is 1 (MSI or INTx mode) then all the fibs are allocated to vector 0. Fixes: 495c0217 "aacraid: MSI-x support" Signed-off-by: Raghava Aditya Renukunta <raghavaaditya.renukunta@pmcs.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/scsi/aacraid/aacraid.h | 2 ++ drivers/scsi/aacraid/commsup.c | 28 ++++++++++++++++++++++++++++ drivers/scsi/aacraid/src.c | 30 +++++++----------------------- 3 files changed, 37 insertions(+), 23 deletions(-) -- 2.7.4